In situ photodynamic therapy

Abstract

The process of photodynamic therapy (PDT) is conducted by the step of: 1) separately encapsulating at least one activation component for said photodynamic therapy process in a liposome; 2) injecting a photosensitizer into a human or animal host; 3) injecting the liposome encapsulated components systemically into the same human or animal host; and 4) heating the site of the tumor to melt the liposome encapsulated components to permit mixing of the activation components. The mixing of the activation components can result in: a) energy transfer to the previously injected photosensitizer; b) emission of light and absorption of said light by the previously injected photosensitizer; and c) direct formation of at least one cytotoxic species that functions against the tumor. The heating of the site of the tumor is accomplished by one of the following methods: laser, ultra sound, radio-frequency or microwave frequency. Photofrin photosensitizer is a preferred photosensitizer.

I claim: 
     
       1. In the process of photodynamic therapy, the improvement comprising: 1) separately encapsulating at least two activation components for said photodynamic therapy process in a liposome;   2) injecting a photosensitizer into a human or animal host;   3) injecting the liposome encapsulated components systemically into the same human or animal host; and   4) heating the site of the tumor to melt the liposome encapsulated components to permit mixing of the activation components.   
     
     
       2. The process of claim 1 wherein the mixing of the activation components results in energy transfer to the previously injected photosensitizer. 
     
     
       3. The process of claim 1 wherein the mixing of the activation components results in the emission of light and absorption of said light by the previously injected photosensitizer. 
     
     
       4. The process of claim 1 wherein the mixing of the activation components results in direct formation of at least one cytotoxic species that functions against such tumor. 
     
     
       5. The process of claim 1 wherein the heating of the site of the tumor is accomplished by one of the following methods: laser, ultra sound, radio-frequency or microwave frequency.   
     
     
       6. The process of claim 1 wherein the photosensitizer is a material capable of being activated by light emission from a luminescent source. 
     
     
       7. The process of claim 1 wherein the photosensitizer is a material capable of accepting energy from the activation components. 
     
     
       8. The process of claim 1 wherein the photosensitizer is a porphyrin. 
     
     
       9. In the process of photodynamic therapy, the improvement comprising: 1) separately encapsulating at least two activation components for said photodynamic therapy process in a liposome;   2) injecting a photosensitizer which comprises a porphyrin into a human or animal host;   3) injecting the liposome encapsulated components systemically into the same human or animal host; and   4) heating the site of the tumor to melt the liposome encapsulated components to permit mixing of the activation components and generation of light which is absorbed by said photosensitizer.